Founded by the Jesuits in 1794, Holy Trinity is the oldest church in continuous operation in the District of Columbia. It has counted presidents among its parishioners, including President John F. Kennedy and his family. Today, over 3,500 families are registered as parishioners, who come from throughout the metropolitan Washington area.

The parish, which shares the Society of Jesus’ mission to serve the faith and to promote justice, has a rich history. One pastor, Jesuit Father Benedict J. Fenwick, became the second Bishop of Boston and founded Holy Cross College. A subsequent pastor, Jesuit Father John McElroy, founded Boston College.

The first church building, which still serves as the parish's chapel, was built in 1794. To meet the needs of the growing Catholic population in the area, parishioners built a second and larger church 35 years later, and this structure remains in use as Holy Trinity's primary place of worship.

In 1862, following the Second Battle of Bull Run during the Civil War, the U.S. government requisitioned the church for use as a military hospital. Following the battle, more than 200 sick and wounded Union soldiers were treated there. The federal government returned the church to the parish in 1863.

Holy Trinity has a longstanding tradition of community worship; the promotion of Jesuit spirituality, especially the Spiritual Exercises of St. Ignatius; educational programs for adults and children; and service to the poor.

The parish’s Holy Trinity School is a co-educational elementary school (Pre-K - 8th) that is committed to the Jesuit traditions of educational excellence, the service of faith and the promotion of justice. The community — school, parish and families — seeks to develop students who will manifest these traditions in an awareness of self, a love of learning and a desire to serve others